Second-language (L2) learners often have difficulty perceiving speech sounds that are not in the sound system of their native language; however perception improves markedly with L2 experience when tested in phoneme discrimination and identification tasks. The main purpose of this research is to investigate speech perception difficulties in tasks in which L2 listeners must attend to higher levels of linguistic processing. Current theories of L2 learning claim that performance on difficult non-native contrasts is influenced by processing level, due to differences in the learned selective attention patterns of native language (L1) v. L2 perceivers. The hypothesis is that performance in a grammaticality task that depends on perceiving difficult vowel contrasts in French will reflect interference from L1 phonological perception patterns in advanced Canadian English L2 learners of French, relative to their performance in an identification task. These differences in perception across tasks must be accounted for by models of cross-language speech perception. A finding that patterns of perception are more influenced by listeners' L1 when attending to higher linguistic levels implies that pedagogical designs for L2 speech learning must use tasks that tap higher processing levels and produce more fully automatic phonological processing of L2 speech. [unreadable] [unreadable] [unreadable]